The times are coming when a machine will stand there and remain at rest. A human being will approach it, knowing that he must make one movement of the hand in this way, another in a definite relation to it, and a third again; and through the pulsations in the air which thus arise out of a certain sign, the motor, being attuned to this particular sign, will be set in motion.
Source: Rudolf Steiner – GA 172 – The Insertion of Early Human Destiny into Extraterrestial Relationships – Dornach, 12th November 1916
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